Instagram and YouTube stars are being investigated for not declaring when they're paid to promote brands

GettyMillie Mackintosh is one celebrity who has not clearly labelled adverts on Instagram.

The UK’s Competition and Markets Authority is investigating celebrities and social media stars for not labelling paid promotions on platforms like Instagram and YouTube.

The competition authority has written to a number of stars it suspects of wrongdoing and could name and shame them before the end of the year.

It is not, at this stage, talking to the social media platforms about whether they are doing enough to stamp out the practice.

Britain’s Competition and Markets Authority has launched an investigation into celebrities and social media stars failing to declare when they are being paid to promote brands on platforms like Instagram.

The Competition and Markets Authority is not, at this stage, talking to social media platforms like Instagram and YouTube about whether they are doing enough to clamp down on poorly labelled ads. Its investigation could broaden, however, depending on its findings.

“If people see clothes, cosmetics, a car, or a holiday being plugged by someone they admire, they might be swayed into buying it,” said George Lusty, the Competition and Markets Authority’s senior director for consumer protection.

“So, it’s really important they are clearly told whether a celebrity is promoting a product because they have bought it themselves, or because they have been paid or thanked in some way by the brand.”